1. Technical Field of the Invention
The invention relates generally to communication systems; and, more particularly, it relates to determining end of an operational window within single user, multiple user, multiple access, and/or MIMO wireless communications.
2. Description of Related Art
Communication systems are known to support wireless and wire lined communications between wireless and/or wire lined communication devices. Such communication systems range from national and/or international cellular telephone systems to the Internet to point-to-point in-home wireless networks. Each type of communication system is constructed, and hence operates, in accordance with one or more communication standards. For instance, wireless communication systems may operate in accordance with one or more standards including, but not limited to, IEEE 802.11x, Bluetooth, advanced mobile phone services (AMPS), digital AMPS, global system for mobile communications (GSM), code division multiple access (CDMA), local multi-point distribution systems (LMDS), multi-channel-multi-point distribution systems (MMDS), and/or variations thereof.
In some instances, wireless communication between a transmitter and receiver is a single-output-single-input (SISO) communication, even if the receiver includes multiple antennae that are used as diversity antennae (i.e., selecting one of them to receive the incoming radio frequency (RF) signals). For SISO wireless communications, a transceiver includes one transmitter and one receiver. Currently, most wireless local area networks (WLAN) (e.g., IEEE 802.11, 802.11a, 802,11b, 802.11g) employ SISO communications.
Other types of wireless communications include single-input-multiple-output (SIMO) (e.g., a single transmitter processes data into RF signals that are transmitted to a receiver that includes two or more antennae and two or more receiver paths), multiple-input-single-output (MISO) (e.g., a transmitter includes two or more transmission paths (e.g., digital to analog converter, filters, up-conversion module, and a power amplifier) that each converts a corresponding portion of baseband signals into RF signals, which are transmitted via corresponding antennae to a receiver), and multiple-input-multiple-output (MIMO) (e.g., a transmitter and receiver each include multiple paths such that a transmitter parallel processes data using a spatial and time encoding function to produce two or more streams of data and a receiver receives the multiple RF signals via multiple receiver paths that recapture the streams of data utilizing a spatial and time decoding function).